#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include "./getch/getch.h"

#define MAXTOKEN  100

enum { NAME, PARENS, BRACKETS };

void dcl(void);
void dirdcl(void);

int gettoken(void);
int tokentype;			// type of last token
char token[MAXTOKEN];		// last token string
char name[MAXTOKEN];		// identifier name
char datatype[MAXTOKEN];	// data type = char, int, etc.
char out[1000];

int main()			// convert declaration to words
{
	while(gettoken() != EOF)	// 1st token on line
	{
		strcpy(datatype, token);	// is the datatype
		out[0] = '\0';
		dcl();			// parse rest of line
		if(tokentype != '\n')
			printf("syntax error \n");
		printf("%s: %s %s\n", name, out, datatype);
	}
	return 0;
}

// dcl: parse a declarator
void dcl(void)
{
	int ns;
	
	for(ns = 0; gettoken() == '*'; )		// count *'s
		ns++;
	dirdcl();
	while(ns-- > 0)
		strcat(out, "pointer to");
}

// dirdcl: parse a direct declarator
void dirdcl(void)
{
	int type;

	if(tokentype == '(')				// (dcl)
	{
		dcl();
		if(tokentype != ')')
			printf("error: missing ) \n");
	}
	else if(tokentype == NAME)		// variable name
		strcpy(name, token);
	else 
		printf("error: expected name or (dcl)\n");
	while((type = gettoken()) == PARENS || type == BRACKETS)
		if(type == PARENS)
			strcat(out, " function returning");
		else
		{
			strcat(out, " array");
			strcat(out, token);
			strcat(out, " of");
		}
}

int gettoken(void)			// return next token
{
	int c, getch(void);
	void ungetch();
	char *p = token;

	while((c = getch()) == ' ' || c == '\t')
		;
	if(c == '(')
	{
		if((c = getch()) == ')')
		{
			strcpy(token, "()");
			return tokentype = PARENS;
		}
		else
		{
			ungetch(c);
			return tokentype = '(';
		}
	}
	else if(c == '[')
	{
		for(*p++ = c; (*p++ = getch()) != ']'; )
			;
		*p = '\0';
		return tokentype = BRACKETS;
	}
	else if(isalpha(c))
	{
		for(*p++ = c; isalnum(c = getch()); )
			*p++ = c;
		*p = '\0';
		ungetch(c);
		return tokentype = NAME;
	}
	else
		return tokentype = c;
}
	
 
